Tectonic and Sedimentary Characteristics and Evolution of the Hefei Basin, China: Implications for Jurassic Hydrocarbon Source Rock Development

The Hefei Basin is an intracontinental basin located at the junction of three major tectonic units, the North China plate, the Dabie orogen and the Yangtze plate. This unique tectonic background controlled the structures and sedimentary sources for the Hefei Basin. The tectonic framework in the Jurassic is typical of foreland basins and can be further divided into wedge top, foredeep, forebulge and post- uplifting units. During the Jurassic, the main sedimentary system in the basin consisted of alluvial fan, fan delta, lacustrine delta and lake, characterized by zonation and controlled by the structural belts. Hydrocarbon source rocks in the Hefei basin were mainly developed during the early to middle Jurassic, and were influenced by depositional setting and tectonic activities constrained by the basin structural framework, depositional environment and paleoclimate. The target source rocks are only associated with the semi-deep lake zone in the lower uplift of the foredeep.